The first version of ASP.NET 1.0 came out almost 14 years ago. Since then many developers have used it to build and run great web applications, and over the years we have added and evolved many, many capabilities to it.

Today we are excited to announce the release of ASP.NET Core 1.0! This new release is one of the most significant architectural updates we’ve done to ASP.NET. As part of this release we are making ASP.NET leaner, more modular, cross-platform, and cloud optimized. ASP.NET Core is now available, and you can start using it today by downloading it here.

ASP.NET Core is an open source web framework for building modern web applications that can be developed and run on Windows, Linux and the Mac. It includes the MVC framework, which now combines the features of MVC and Web API into a single web programming framework. ASP.NET Core is built on the .NET Core runtime, but it can also be run on the full .NET Framework for maximum compatibility.

We challenged everything instead of delivering an incremental update so you can have an extremely modular, fast and lightweight platform perfect for the new era of software development where monolithic applications are replaced by small, autonomous services that can be deployed individually. All of that while keeping and extending what .NET is best for: developer productivity, and modern languages and libraries.

With ASP.NET Core we are making a number of architectural changes that makes the core web framework much leaner (it no longer requires System.Web.dll) and more modular (almost all features are now implemented as NuGet packages – allowing you to optimize your app to have just what you need). With ASP.NET Core you gain the following foundational improvements:

Build and run cross-platform ASP.NET apps on Windows, Mac and Linux

Built on .NET Core, which supports true side-by-side app versioning

New tooling that simplifies modern Web development

Single aligned web stack for Web UI and Web APIs

Cloud-ready environment-based configuration

Built-in support for dependency injection

Tag Helpers which makes Razor markup more natural with HTML

Ability to host on IIS or self-host in your own process

The end result is an ASP.NET that you’ll feel very familiar with, and which is also now even more tuned for modern web development.

This is a 1.0 product which means it is just the beginning and does not have all the functionality of ASP.NET 4.x stack. For example, features like SignalR and Web Pages will come later in the year and other features like Web Forms which are deeply tied to System.Web will remain in the .NET 4.x framework. If you are an existing ASP.NET 4.x developer do not feel rushed to move to ASP.NET Core, we still plan to update Web Forms, MVC, Web Pages, SignalR on .NET 4.x as well.

If you are not a .NET developer, now it’s a great moment to try it. You can enjoy the productivity and power of .NET with no constraints, on any OS, with any tool and for any application. All of that fully open source, developed with the community and with Microsoft’s support.